Cigarette-making machines of the continuous rod type



Feb. 6, 1962 F. A. M

LABBE CIGARETTE-MAKING MACHINES OF THE CONTINUOUS ROD TYPE Filed March 16. 1959 O O O O O O O O O O OO O O O O O O O 4 Sheets-Sheet 1 OO O u/wu, 4, fi 1 IN VEN TOR F. A. M. LABBE'.

Feb. 6, 1962 CIGARETTE-MAKING MACHINES OF THE CONTINUOUS ROD TYPE Filed March 16, 1959 4 Sheets-Sheet 2 IA/VENTOR a; I i/ 51 JMGZ fil 1 a ATTORNEY Feb. 6, 1962 F. A. M. LABBE 3,019,793

CIGARETTE-MAKING MACHINES OF THE CONTINUOUS ROD TYPE Filed March 16, 1959 4 Sheets-Sheet 3 INVENTOR ATTORIVE Y Feb. 6, 1962 F. A. M. LABBE 3,019,793

CIGARETTE-MAKING MACHINES OF THE CONTINUOUS ROD TYPE Filed March 16. 1959 4 Sheets-Sheet 4 A TTORNE Y3 United States This invention concerns improvements in or relating to apparatus for forming a tobacco filler in a tobacco-manipulating machine such as a continuous rod cigarette-making machine.

United States applications Serial Nos. 479,573, 702,104 and 738,805, filed January 3, 1955 (now abandoned), December 11, 1957, and May 29, 1958, respectively, disclose cigarette-making machines in which a tobacco filler is formed on a perforated conveyor band by means of a stream of air fiowing at high velocity through a passage towards and through the conveyor band so as to carry tobacco particles through the passage in substantially separated form. in those machines, the air stream is wholly confined laterally by the passage, and all the air which passes through the passage leaves the passage by flowing through the perforated conveyor band and through the tobacco on the conveyor band.

According to the present invention there is provided in a tobacco-manipulating machine such as a continuous rod cigarette-making machine, apparatus for forming a tobacco filler, comprising a conveyor band on which the filler is formed, a passage extending towards said conveyor band, tobacco-feeding means to feed tobacco into the said passage, and means to cause a stream of air to flow through the passage towards the conveyor band so as to convey the said tobacco through the passage and impel it on to the conveyor band or on to tobacco already on the conveyor band, the said passage having a side opening through which air can escape from the passage so as to be separated from the tobacco While the latter continues to move towards the conveyor band. The apparatus may comprise means to draw air from the passage through the said opening. The'said side opening may be provided witha number of guide elements which are inclined to the passage so'as to guide air out of the passage in a rearward direction considered in the direction in which air moves through the passage.

The said conveyor band may be porous or perforated,

to enable air to pass through it. Suction means may be provided to draw air through the conveyor band. The suction means may be arranged to exert pressure on the filler being formed on the conveyor band so as to determine the density of the filler so formed.

' The said suction means may be arranged to exert sufficient pressure on the filler being formed to cause the latterto be compressed to a density such that the filler can withstand the impact of tobacco particles impelled against it, with-out undue disturbance of the tobacco which constitutes the partly formed filler.

The said suctiorrmeans may be arranged to exert sufl"r-' cient pressure on the filler being formed to compress the latter to a density at least half that required in the final tobacco product, e.g. in a cigarette produced from the filler.

Further according to the invention there is provided in a tobacco-manipulatingmachine such a a continuous rod cigarette-making machine, apparatus for forming a tobac' co filler, comprising a perforated conveyor band arranged to move lengthwise and on which the tiller is formed, a passage extending towards a substantial length of said conveyor band, means to cause a stream of air to flow through the passage towards said conveyor band, tobaccofeeding means to feed tobacco into said passage for conveyance by said air stream towards the conveyor band, suction means to draw air from said passage through said band and to exert suctional pressure on tobacco to hold the latter to the band, an opening in a side of the passage through which air approaching the band can escape, and means to draw air from the passage through the said opening, whereby air can be caused to flow through the pars sage at a velocity such as to impart a high velocity to the tobacco conveyed thereby, while only a desired proportion or" the air is caused to pass through the conveyor 7 band and through tobacco thereon. The said opening may extend a substantial distance along the length of the passage, the apparatus also comprising a suction chamber communicating with the passage through the said opening, wherein the said suction chamber increases in size in the direction of movement of the conveyor band from one end of the passage to the other, whereby less air is drawn from a part of the passage where the conveyor band carries little tobacco, than from a part where the conveyor band carries more tobacco, and whereby differences in the suctional pressure exerted on the partly formed'filler in the passages at diiierentrparts along the length of the passage can be reduced.

The said tobacco feeding means may be arranged to feed tobacco into the stream of air in the form of substantially separated particles, and the air stream maycause the said particles to move through the passage with-- out deceleration such as would cause agglomeration or bunching of the particles in the passage to any substantial extent. The stream of air may be caused to move through the passage with a velocity such as to increase the speed of tobacco particles fed into the passage and thereby causes tobacco particles to move apart from one another in the passage.

Further according to the invention there is a tobacco-manipulating machine such as a continuous rod cigarette-making machine, apparatus for forming a'tobacco filler, comprising a perforated conveyor band on which the filler is formed and through which air can pass, a passage extending to the conveyor band and having opposed side walls, means to feed tobacco particles into a the passage, means to cause a stream of air to flow through the passage towards the conveyor band so as to impel the tobacco particles on to the conveyor band or on to tobacco already on the conveyor band, the velocity ofthe air stream in the passage being such as to effect a rapid increase in the speed of tobacco particles so impelled andthereby cause particles to move apart from one another in the passage, an air outlet in a side wall of the passage and means to cause a desired proportion of the air which passes through the passage to leave the latter by passing through the said outlet, whereby the air stream is caused to enter the passage at a rate independent of the resistance offered by the conveyor band and the tobacco thereon to the flow of air therethrough.

Still further according to the invention there is provided in a tobacco-manipulating machine such as a continuous rod cigarette-making machine, apparatus for forming a tobacco filler, comprising a conveyor band on which hte filler is formed and supported, a passage extending downwardly to the conveyor band and having opposed side walls, an opening in aside wall near the conveyor band, means to feed tobacco particles into the passage, and means to cause a stream of air to flow through the passage towards the conveyor band so as to impel the tobacco particles on to the conveyor bandor on to tobacco already on the conveyor band, and so as to leave the passage by passing through the said opening while the tobacco particles continue to move towards the conveyor band.

Apparatus in accordance with the invention will now Patented Feb. 6, 1962 provided inv be described by way of example with reference to the accompanying drawings, in which:

FIGURE 1 is a sectional end view of part of a cigarette-making machine, showing arrangements for feeding tobacco and schematically illustrating arrangements for moving air through parts of the machine,

FIGURE 2 is a front elevation, partly in section and partly broken away, showing some of the apparatus illust'rated in FIGURE 1, but to a larger scale,

FIGURE 3 is a section on the line III-11 FIGURE 2, to an enlarged scale,

FIGURE 4 shows, to a greatly enlarged scale, a fragment of a perforated conveyor band, and

FIGURES 5 and 6 are sectional end elevations illustrating respectively two alternative constructions.

Referring first particularly to FIGURES l and 2, the tobacco-feeding apparatus includes a carded conveyor drum 1, on to whose upper surface cut tobacco is fed by' mechanism such as that disclosed in US. Patent No. 2,994,489. A carded refuser roller 2 is arranged to brush back surplus tobacco. A picker roller 3 is arranged to pick tobacco from the drum 1, and to impel it over a concave guide plate 4.

Beyond the plate 4 is a perforated, rotatable cylinder 5 arranged to rotate about two fixed elements 6 and 7-. The cylinder 5 is located at the entrance to an air duct 8 comprising three adjacent sections 9, 10 and 11, as best seen in FIGURE 2.

Beyond the cylinder 5 and duct 8 is a narrow passage 12 formed by side walls 13 and 14, and end walls 15 and 16, FIGURE 2.

At the top of the passage 12 an endless metal conveyor band 20, provided with perforations 21 as shown, greatly enlarged, in FIGURE 4, passaes over pulleys 22, 23, FIGURE 2 and over a shoe 24 which is adjustable to take up the slack in the band.

The band extends directly beneath a suction cham ber 25, the edges of the band, as shown in FIGURE 3, engaging shoulders formed on opposed members 26 which form a conduit leading to the suction chamber 25.

Close to the inlet to the passage 12 is a series of vanes 28, inclined as shown in FIGURE 2, which are provided to guide air towards the left, FIGURE 2, as it enters the passage.

A grill 29 extends beneath the perforated cylinder 5 and the passage inlet.

The apparatus so far described is similar to the apparatus disclosed in United States application Serial No. 738,805.

In the present construction, the side wall 14 of the passage 12 has, at a position near its upper end, an opening 31, see FIGURE 3, by which the passage 12 communicates with a suction chamber 32. A grill 33 made of expanded metal extends over the opening, and as can be seen in FIGURE 3, the grill is formed with apertures 34 which are bounded by parts 35 which slope downwardly away from the passage 12. The parts 35 of the grill form louvres or guide elements by which air escaping from the passage 12 through the opening 31 into the suction chamber 32 is guided out of the passage downwardly, that is, in a rearward direction considered in the direction of movement of the air upwardly through the passage 12.

As shown in FIGURE 2, the suction chamber 32' is tapered, increasing in depth from right to left in FIG- UR'E 2, that is, in the direction of movement of the conveyor band 20. The width of the chamber is uniform throughout its length.

A pipe 37 connects the larger end of the chamber 32 with the duct 8.

In FIGURE 1 the connection between the passage 12 and the air duct 8 to the pipe 37 is illustrated schemati- (rally, as are the arrangements for moving air through the machine. Further, the opening 31, suction chambe: 32, and grill '33 illustrated in FIGURE 3 are not shown in FIGURE 1.

The means for causing air to flow through the machine will now be briefly described with particular reference to FIGURE 1.

The suction chamber 25, above the conveyor band 20, I

curved plate 49, a sheet 55) of expanded metal, and a chamber 51 to receive short particles of tobacco which may be in the air. The plate 49 is apertured to allow air to fiow over an edge of the plate into the chamber 51, and out of the chamber through a central aperture.

Air flows upwardly through the expanded metal sheet 50 and through the grill 29 to be drawn into the passage 12 and the duct 8.

The air discharged by the fan 41 passes through a conduit 53 to a multi-unit cyclone 54 by which, after removal of dust, the air is discharged to atmosphere. Accordingly the air drawn into the passage 12 and air duct 8 consists of air from the diffuser 35 mixed with atmospheric air.

A further dust-separating device 55 is provided in the conduit 53 and is connected by a pipe 56 to the channel through which the band 20' moves, at a position beyond the passage 12 (i.e, to the left of the end Wall 13 in FIGURE 2) so as to convey a certain amount of short tobacco particles to the tobacco filler. This can be controlled or put out of action if desired by a valve 57.

The air drawn into the duct 8 through the perforated cylinder 5 deflects the tobacco impelled over the plate 4 by the picker roller 3 so that the tobacco particles move in a curved path into the entrance of the passage 12, as described in United States application Serial No. 738,805.

From the above description it will be seen that some of the air which passes up the passage 12 is drawn through the conveyor band 20 and suction chamber 25 by the fan 41, while some is drawn through the opening 31, the suction chamber 32, and the pipe 37 by the fan 43, together with the air drawn through the perforated cylinder 5 into the duct 8.

Referring to FIGURE 2, a trimming device comprising a pair of discs 60 (only one of which is visible in the figure) is located beyond the passage 8 to trim the tobacco filler formed on the conveyor band 20 and held thereon by suction. Beyond the trimming device a paper web 61 is led over a tape 62 which runs in a trough 63, the paper web being led directly beneath the conveyor band 20 at a position where the latter still extends beneath the suction chamber '25. Folding, gumming, and sealing devices (not shown) are provided to wrap the paper web around the tobacco filler to form a continuous cigarette rod.

A pivoted flap 64 is located at the position where the conveyor band so carries the tobacco filler out of the passage 12, and acts to prevent or hinder air from flowing into the passage from atmosphere through the gap between the tobacco filler and the end wall 13.

The operation of the apparatus so far described is as follows. Cut tobacco fed to the carded drum 1 is picked from it and impelled over the plate 4'by the picker roller 3 in substantially the form of separated particles. Air flowing upwardly through the grill 29, as described above, flows partly through the perforated rotating cylinder 5 and partly into the passage 12. The air flowing through the cylinder 5 acts to deflect tobacco particles so as to make them travel in a curved path to enter the passage 12, through which they are carried upwardly towards the conveyor band 20 to form a tobacco filler thereon, in the general manner described in United States application Serial No. 738,805.

The tobacco thus fed to the conveyor band 20 builds up on the band, as the latter travels from right to left, FIGURE 2, and forms a filler, the tobacco being held by suction to the band as the filler is formed. The suction exerted on the filler through the perforated conveyor band is Such as to compress the filler laterally (that is, in a direction towards the band) to a density at least half that required in the final cigarette rod and cigarettes produced from the rod. By compressing the tiller by suction in this way during its formation, the tobacco in the partly formed filler is better able to withstand the impact of tobacco particles which are impelled against it at high velocity by the air stream to continue the formation of the filler. Moreover, since the filler so formed is compressed to a substantial degree, the mechanical work required to compress the filler to rod size preparatory to enclosing it in the cigarette-paper Web is considerably reduced.

The air stream flowing through the passage 12 is required to move at high speed in order to cause tobacco particles to move through the passage up to the conveyor hand without deceleration such as would cause them to bunch together or agglomerate. Further, the air velocity should be high enough to impart sufficient velocity to tobacco particles entering the passage to cause them to move apart from one another, by rapidly increasing the speed of successive particles as they enter and move upwardly through the passage. This produces very beneficial effects in the formation of the filler, which can be built up more uniformly and more satisfactorily if the tobacco arrives at the travelling conveyor band 26, and at the partially formed filler carried by the band, as far practicable in the form of discrete, separate particles. This method of forming a tobacco filler is fully described and explained in United States application Serial No. 738,805. In the construction disclosed in that application, the velocity with which air can be caused to flow up the passage (corresponding to the passage 12 in the present construction) is limited by the resistance offered to the air flow by the tobacco on the conveyor band (corresponding to the band 20 in the present case) as Well as the resistance of the band itself.

By the construction described and illustrated herein, it is possible to cause air to fiow through the passage 12 at a greatly increased velocity, since the air passing through the passage leaves the passage not only through the conveyor band 20, but also by the opening 31 in the side wail 14. Thus the proportion of air drawn through the conveyor band 26) by the fan 41, to that of the air drawn through the opening 31 by the fan 53, can be so chosen as to produce an air stream of very high velocity through the greater part of the height of the passage 12, such as to impel tobacco particles towards the conveyor band 20 at high speed. A substantial proportion of the air is drawn out of the passage through the opening 31, but the momentum of the tobacco particles is such as to carry them up to the conveyor band 2%), or to the tobacco already on the band, with suflicient speed.

In the construction being described, it is found satisfactory to regulate the airflow so as to produce in the passage 12 an upward air stream whose velocity immediately below the opening 31 is about 80 feet per second, while above the opening 31 its velocity'is about 36 feet per second. In that arrangement, therefore, it will be seen that'about 55' percent of the air that flows up the passage 12 is drawn through the opening 31, while only about 45 percent flows through the perforated conveyor band 21 As stated above, the vanes 28 at the inlet to the passage 12 guide the entering air towards the left as viewed in FIGURE 2. This gives the air moving upwards in the passage a component of movement in the direction of movement of the conveyor band 20. As explained in United States application Serial No. 738,805-this arrangement makes it possible to cause the fast-moving to bacco particles to reach the conveyor band with substantially no movement relatively to the conveyor band considered in the direction of movement of the latter. That is the effect can be virtually the same as if the conveyor band were stationary and the tobacco particles travelled towards it in directions substantially normal to the band. This has a beneficial effect on the formation of the filler, since it avoids or greatly reduces irregularities which have in the past been caused, when tobacco is showered by gravity on to a band which is moving past the falling tobacco, by upstanding parts of a tobacco filler intercepting falling particles and thus causing undue accumulation of tobacco in front of and on top of such upstanding parts, withcorresponding sparsity behind such parts.

The arrangement according to the present invention by greatly increasing the speeds which can be attained by the tobacco particles in their travel to the conveyor band, makes it possible to obtain the benefits just described, even at very greatly increased speeds of operation of the machine. increased in order to increase the rate of output of the machine, the speed at which the air carries the particles through the passage towards the partly formed filler can be correspondingly increased. As pointed out above, the limitations on the speed of the air through the passage which exist in a construction in which the only outlet for air from the passage is through the conveyor band and through the tobacco on the band, are removed by the pro vision of an additional outlet, namely the opening 31. Thus the speed of the air stream through the passage can be increased so as to maintain (at any rate to a very great degree) the advantages just described, for virtually any increase in the speed of the conveyor band.

As pointed out above, the suction chamber 62 increases in depth and volume from right to left in FIGURE 2. This is because the quantity of tobacco at any instant tobacco is just reaching a part of the conveyor band which has just entered the passage, that is at the extreme righthand end of the passage as viewed in FIGURE 2. Accordingly the suction chamber 32 is constructed so that its capacity for air increases'along the length of the passage so that as the resistance of the tobacco to the flow of air through the band 20 increases, more air can flow through the opening 31. By this arrangement, differences in the pressure drop across the tobacco at different positions along the length of the conveyor band 20 in the passage 12, due to the differing quantities of tobacco on the band at those positions, can be substantially reduced, and the suctional pressure exerted on the partly formed tobacco filler can thus be made more nearly uniform along the whole length of the passage.

In the construction described andillustrated, the crosssectional size of the suction chamber 32 varies from about 31 square centimetres at its smaller end to about 51 square centimetres at its larger end.

Referring now to FIGURE 5, this shows diagrammatically an alternative construction in which a passage 71 formed by side walls 72 extends downwardly towards a trough 73 in which runs a conveyor band 74, formed by Thus if the speed of the conveyor band 20 is suction 'fan, not shown, are provided alongside the side walls of the passage to draw air from the passage through the openings 75.

Provision is made for a stream of air to be directed downwardly at high velocity through the passage, and for tobacco particles to be fed into this downwardly directed air stream for conveyance to the conveyor band 74. In this construction, the whole of the air flowing through the passage is drawn off through the openings 75, being directed outwardly, and rearwardly considered in the direction of the air stream in the passage, by the guide elements 75a. The tobacco has sufficient momentum to continue towards the band 74 at high velocity. The air is directed through the passage with sumcient velocity to impart to the tobacco particles a velocity high enough not only to prevent them from agglomerating or bunching together in the passagewhile travelling towards the conveyor band, but also to cause them to move apart. For this purpose the air stream may be given a velocity in the passage of about 30 feet per second.

FIGURE 6 illustrates a further alternative construction in which the passage 71 extends downwardly to the conveyor band 74, but in this case the band 74 is provided with perforations 83 and runs over a suction chamber 84 from which air is drawn by a suction fan through a duct 85. In this case, as in the construction illustrated in FIG- URES 1 to 4, air may be caused to flow through the passage at a very high velocity, since a proportion of the air is drawn from the passage through the openings 75, andthrough suction chambers 76 and ducts 77 as in the construction shown in FIGURE 5.

What I claim as my invention and desire to secure by Letters Patent is: i

1. In a tobacco-manipulating machine such as a continuous rod cigarette-making machine, apparatus for forming a tobacco filler, comprising a conveyor on which the filler is formed, a pair of opposed walls defining an enclosed passage and extending to said conveyor at opposite sides thereof, tobaccofeeding means to feed tobacco into the said passage, and air-impeding means to cause a stream of air to flow through the passage at high velocity towards the conveyor in a direction such as to cause the air to convey the said tobacco through the passage and impel it on to the conveyor or on to tobacco already on the conveyor, the said pas-sage having a side opening through which air can escape from the passage so as to be separated from the tobacco while the latter continues to move towards the conveyor, the said air-impelling means being arranged to impart to the air a velocity through the passage such that tobacco is impelled by the air past the said side opening to reach the conveyor.

2. Apparatus as claimedin claim 1, comprising means to draw air from the passage through the said opening.

3. Apparatus as claimed in claim 1, wherein the said side opening is provided with a number of guide elements which are inclined to the passage so as to guide air out of the passage in a rearward direction considered in the direction in which air moves through the passage.

4. Apparatus as claimed in claim 1, wherein the said conveyor is porous or perforated, to enable air to pass through it.

5. Apparatus as claimed in claim 4, wherein suction means is provided to draw air through the conveyor.

' 6. Apparatus as claimed in claim 5, wherein the suction means is arranged to exert pressure on the filler being formed on the conveyor so as to compress the tobacco in the filler so formed.

7. Apparatus as claimed in claim 6, wherein the said suctionmeans is arranged to exert sufrlcient pressure on the filler being formed to cause the latter to be compressed to a density such that the tiller can withstand the impact of tobacco particles impelled against it, without undue disturbance of the tobacco which constitutes the partly formed filler.

8. In a tobacco-manipulating machine such. as a continuous rod cigarette-making machine, apparatus for forming a tobacco filler, comprising a perforated conveyor arranged to move lengthwise and on which the filler is formed, a pair of opposed walls defining an enclosed passage and extending to a substantial length of said conveyor at opposite sides thereof, means to cause a stream of air to flow at high velocity through the passage towards said conveyor, tobacco-feeding means to feed tobacco into said passage for conveyance by said air stream towards the conveyor, suction means to draw air from said passage through said conveyor and to exert suctional pressure on tobacco to hold the latter to the conveyor, an opening in a side of the passage throughwhich air approaching the conveyor can escape, and means to draw air from the passage through the said opening, whereby air can be caused to flow through the passage at a velocity such as to impart a high velocity to the tobacco conveyed thereby, while only a desired proportion of the air is caused to pass through the conveyor and through tobacco thereon.

9. Apparatus as claimed in claim 1, wherein the said opening extends a substantial distance along the length of the passage, and comprising a suction chamber communicating with the passage through the said opening, wherein the said suction chamber increases in size in the direction or" movement of the conveyor from one end of the passage to the other, whereby less air is drawn from a part of the passage Where the conveyor carries little tobacco, than from'a part where the conveyor carries more tobacco, and whereby differences in the suctional pressure exerted on the partly formed filler in the passages at different parts along the length of the passage can be reduced.

10. In a tobacco-manipulating machine such as a con tinuous rod cigarette-making machine, apparatu for forming a tobacco filler, comprising a perforated conveyor on which the tiller is formed and through which air can pass, a passage extending to the conveyor and having opposed side walls, means to feed tobacco particles into the passage, means to cause a stream of air to flow through the passage towards the conveyor so as to impel the tobacco particles on to the conveyor or on to tobacco already on the conveyor, the last-named means being arranged to impart a velocity to the air stream in the passage such as to effect a rapid increase in the speed of tobacco particles so impelled and thereby cause particles to move apart from one another in the passage, an air outlet in a side wall of the passage, and means to cause a desired proportion of the air Which passes through the passage to leave the latter by passing through the said outlet, whereby the stream is caused to enter the passage at a rate independent of the resistance ofiiered by the conveyor and the tobac-co'thereon to the flow of air therethrough.

11. In a tobacco-manipulating machine such as a continuous rod cigarette-making machine, apparatus for forming a tobacco filler, comprising a conveyor on which the tiller is formed and supported, a passage extending downwardly to the conveyor and having a pair of opposed side walls extending to the conveyor at opposite sides thereof, an opening in a side wall near the conveyor,

means to feed tobacco particles into the passage, and

means to cause a stream of air to fiow through the passage towards the conveyor so as to impel the tobacco particles on to the conveyor or on to tobacco already on the conveyor, and so as toleave thepassage by passing through the said opening while the tobacco particles con: tinue to move towards the conveyor.

12. In a continuous rod cigarette-making machine, apparatns for building up a continuous tobaccofiller on a moving conveyor by feeding tobacco particles to it at high speed by means of a high speed air stream, comprising a conveyor having a-moving tobacco receiving surface, opp osed walls defining anair conduit and ex-. tending to opposite sides of, and along a substantial the said air conduit toward the said surface, so as to impel tobacco particles at high speed to and against said surface, and venting means defining an air escape outlet located at a side of said conduit in a position close enough to the said surface to ensure that tobacco particles due to their high momentum continue their movement and reach the said surface at high speed.

13. Apparatus as claimed in claim 12, wherein the conveyor is air perviou's, and comprising means to draw air from the passage through the conveyor and through the said side opening respectively in desired proportions.

14. Apparatus as claimed in claim 13, comprising guide means to cause the air stream to move through the conduit in a direction inclined to the length of the said surface, so that the air moves toward the said surface with a component of movement in the direction of movement of the said surface.

15. In a continuous rod cigarette-making machine, a conveyor having a moving tobacco receiving surface, opposed walls defining an air conduit extending to, and along a substantial length of, the said conveyor, and having an inlet for air remote from the conveyor, and an air escape outlet located at a side of the conduit close to the conveyor, air-impelling means to impel air as a stream through said inlet and through said conduit, said air-impelling means including means to draw air from said conduit through said escape outlet, and means to feed tobacco into the air stream at a position such that the tobacco is entrained by the air stream and impelled through the conduit to the conveyor, the said air-impelling means, together with the opposed walls, being armeans to draw air from the conduit through said air 7 ranged in cooperation to impart to the air stream a high velocity such that the air impels the tobacco at suflicient speed to cause the tobacco to travel past the air escape outlet and reach the conveyor.

16. In a continuous rod cigarette-making machine, an air pervious conveyor having a moving air pervious tobacco receiving surface, opposed walls defining an air conduit extending to, and along a substantial length of,

the conveyor, and having an inlet for air remote from the conveyor, and an air escape outlet located at a side of the conduit close to the conveyor, air-impelling means to impel air as a stream through the said inlet and through the conduit, said air-impelling means including pervious conveyor, and means to draw air from the conduit through said air escape outlet, means to feed tobacco into the air stream at a position such that the tobacco is entrained by the air stream and impelled through the conduit to build up on the conveyor and form a tobacco stream thereon, the said air-impelling means being arranged in cooperation with the said opposed walls to impart to the air stream a velocity such that air is drawn into and through the conduit at a rate in excess of that at which it passes through the conveyor and through the tobacco thereon, the excess air being drawn from the conduit through the air escape outlet.

References Cited in the file of this patent UNITED STATES PATENTS 

